|Publication number||US5911690 A|
|Application number||US 08/849,285|
|Publication date||15 Jun 1999|
|Filing date||1 Dec 1995|
|Priority date||1 Dec 1994|
|Also published as||DE4442855A1, DE4442855B4, WO1996016590A1|
|Publication number||08849285, 849285, PCT/1995/4753, PCT/EP/1995/004753, PCT/EP/1995/04753, PCT/EP/95/004753, PCT/EP/95/04753, PCT/EP1995/004753, PCT/EP1995/04753, PCT/EP1995004753, PCT/EP199504753, PCT/EP95/004753, PCT/EP95/04753, PCT/EP95004753, PCT/EP9504753, US 5911690 A, US 5911690A, US-A-5911690, US5911690 A, US5911690A|
|Original Assignee||Reinhold Kintza, Gerhard Rall|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (47), Non-Patent Citations (4), Referenced by (33), Classifications (21), Legal Events (5)|
|External Links: USPTO, USPTO Assignment, Espacenet|
1. Field of the Invention
The invention relates to the use of a pulse oximetry sensor device during birth.
2. Description of the Related Art
A pulse oximetry sensor device for obstetric use is known for example, from DE 43 04 693. Such a sensor device is applied during birth on the leading part of the fetus. The sensor device includes a light emitter and a receiver. The light emitter sends a wavelength that radiates through the tissue of the fetus and is then picked up at least in part by the receiver. At the same time, the EKG of the fetus is measured. In order to be able to draw conclusions about the status of the fetus during birth, the signal occurring during a heart beat between diastole and systole is measured by the receiver. This measurement utilizes the absorption change caused by the arterial inflow of the blood as an indicator for the current fetal status.
During birth, a midwife needs additional information about the labor activity of the birthing mother. Data about the duration, starting time, peak, and end of a contraction are needed. If a midwife determines irregularities, this may be an indication of complications, so that the midwife must call in a physician who will induce further examination.
The use of intrauterine pressure catheters for measuring the labor activity is known. These pressure catheters are placed as a fixation device for standard pulse oximetry sensors between the uterus and fetus and are anchored there by an increase in volume. The catheter's balloon is used for measuring the intrauterine pressure by conducting the pressure to the outside via a tube and measuring the change in pressure at the tube connection. A disadvantage that may occur in the process is that the tube is clamped off during a contraction, so that differential signals can no longer be transmitted.
There is also a risk that germs are introduced into the uterus when inserting the catheter.
The present invention is based on the task of creating a process for recording the maternal labor activity that supplies reliable signals so that a midwife receives measuring values with clear meanings.
According to the present invention, this task is realized by using a pulse oximetry sensor device to measure the change in the oxygen content in the fetal blood during birth. The pulse oximetry sensor device is provided with at least one light emitter and one receiver, connector with an analyzing device, and attached on the leading part of the fetus for measuring the maternal labor activity.
The invention thus uses pulse oximetry in order to obtain information about the maternal labor activity. While in the past pulse oximetry has been used exclusively for monitoring the fetal status via pulse-synchronous pulse oximetry signals, experts were not able to recognize that pulse oximetry also can be used to obtain information about the status of the parturient.
If the pulse oximetry sensor device is attached, for example, to the scalp of the fetus located inside the opening of the cervical os, the blood volume in this part of the scalp rises during a contraction. The pressure between the cervical os and the fetal scalp is so high during a contraction that the venous backflow of the fetal blood is hindered, but is not sufficient to suppress the arterial inflow. The greater blood volume causes greater light absorption and a change in the sensor signal.
If the sensor device is located below the cervical os within the cervix, the opposite effect may occur. The fetal blood is pushed from the fetal tissue during a contraction, so that the light absorption measured by the sensor device decreases.
Thus, reliable signals about the maternal labor activity are always received. Good signals are even received if the fetus changes position during birth.
In a preferred method, the pulse oximetry sensor device can also be used to measure the fetal EKG. In this way, information about the fetal blood flow characteristics during contractions can be gained simultaneously. It is, for example, possible to display the fetal pulse-dependent or pulse-synchronous pulse oximetry signals in a first track, and the pulse oximetry signals for the mother's contractions in a second track.
According to another preferred method, the light emitter is able to output at least one wavelength at which the absorption of the oxygen-rich and oxygen-poor hemoglobin in the fetal blood is approximately equal. This essentially suppresses a signal change as a result of a change in the blood oxygen content. The point at which the absorption of the oxygen-rich hemoglobin (oxyhemoglobin) and oxygen-poor hemoglobin (deshemoglobin) are equal, is also called the isosbestic point.
In a variation of the invention, at least one wavelength emitted by the light emitter is approximately 805 nm. This wavelength is in the range of the isosbestic point. It makes it possible to obtain particularly clear and reliable signals.
In regard to the various types of hemoglobin with unique absorption spectra present in the blood, it is particularly beneficial if a wavelength is emitted at which the greatest possible number of hemoglobin types have the same absorption, or at which the absorption losses are as close together as possible.
The invention will be described in greater detail with reference to the accompanying drawing wherein an exemplary embodiment of the present invention is illustrated, and wherein:
FIG. 1 shows a cross section through a pulse oximetry sensor device attached to the fetal scalp and suitable for use according to the invention, and
FIG. 2 shows a cross section of the abdomen of a parturient with a pulse oximetry sensor device attached to the fetal scalp.
FIG. 1 shows a pulse oximetry sensor device 1 as known from P 43 04 693, with an approximately round carrier 2. The carrier 2 has a centrically arranged attachment zone 3 with a wire spiral 4 and a metal plate 5. Metal plate 5 and wire spiral 4 are electrically insulated from each other. The metal plate 5 has a coupling part 6 located centrically on its top part.
The carrier 2 is provided around the attachment zone 3 with an elastic marginal zone 10, into which two light emitters 7 and a receiver 8 are imbedded. Light emitter 7 and receiver 8 adjoined the underside 9 of the sensor device 1 and are connected to electrical conductors 11 that exit from the top side of the sensor device 1.
In the same manner, the metal plate 5 and the wire spiral 4 are each connected to an electrical conductor 11 that exits from the top of the sensor device 1.
The wire spiral 4 projects from the underside 9 with approximately one winding turn. In FIG. 1, the wire spiral 4 is twisted with the lowest portion winding into the scalp 12 of a fetus. The carrier 2 hereby rests with a preload with its elastic marginal zone 10 on the fetal tissue 12.
Light emitter 7 and receiver 8 are located close to the scalp 12. The elasticity of the marginal zone 10 ensures that it is always in contact with the scalp 12 so that no light can penetrate from the outside between the light emitter 7, receiver 8, and the scalp 12.
FIG. 2 shows the abdomen 13 of a parturient in which the cervical os 14 is already open, and the amniotic sac 15 has burst. The fetal head 16 is partially visible through the cervical os 14.
The sensor device 1 from FIG. 1 is passed through the cervical os 14 and attached to the fetal scalp 12. An electrical conductor 11 connects the sensor device 1 with an analyzing device 17.
The use of the sensor device according to one embodiment of the present invention is explained in more detail below.
During birth, after the opening of the cervical os 14 and the bursting of the amniotic sac 15, the sensor device 1 is twisted with the wire spiral 4 into the scalp 12 of the fetus by means of a handling device that engages with the coupling part 6 of the sensor device 1. The wire spiral 4 is twisted inward until approximately one winding is twisted into the scalp 12, and the elastic marginal zone 10 rests with an elastic preload on the scalp 12. The electrical conductors 11 are passed to the outside through the cervical os 14 and are connected to an analyzing device 17.
When a contraction occurs, the blood stagnates in the area of the cervical os 14 because the venous backflow is prevented, but the arterial inflow is maintained at least in part. When the fetal tissue is irradiated by the light emitter 7, significantly more light is absorbed by the stagnating blood than in the absence of contractions. The signal obtained in the manner therefore differs from the signal obtain in the absence of contractions and appears as a peak on a recording strip of the analyzing device 17.
If the sensor 1 rests directly against the maternal tissue, the pressure of a contraction causes the blood to escape from this part of the fetal tissue. The absorption of the light through the blood is therefore smaller, so that a signal that differs from that in the absence of contractions is generated and is recorded by the recording medium of the analyzing device as a deviation.
The obtained signals are recorded along a time axis on a recording strip or are displayed on a monitor. Starting from an approximately straight line, each contraction appears like a wave crest. Based on the succession over time and the shape of the wave crests, the start, duration, peak and end of a contraction can be determined.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US4281659 *||12 Mar 1979||4 Aug 1981||Roche Medical Electronics Inc.||Applying and securing percutaneous or transcutaneous probes to the skin especially for fetal monitoring|
|US4299232 *||19 Jun 1979||10 Nov 1981||Mario Zilianti||Bipolar electrodes for fetal heart-rate recording during labor|
|US4476871 *||23 Apr 1982||16 Oct 1984||American Home Products Corporation||Monitoring of cervical dilatation during labor|
|US4658825 *||24 Feb 1986||21 Apr 1987||International Biomedics, Inc.||Spiral probe for simultaneous electrical and chemical monitoring of a fetus|
|US4798588 *||27 Mar 1987||17 Jan 1989||Rene Aillon||Central venous pressure catheter and method for using|
|US4825879 *||8 Oct 1987||2 May 1989||Critkon, Inc.||Pulse oximeter sensor|
|US4913151 *||5 Jan 1989||3 Apr 1990||Norio Harui||Tool for placement of a monitoring probe in the scalp of a fetus|
|US4936306 *||27 Nov 1985||26 Jun 1990||Doty James R||Device and method for monitoring evoked potentials and electroencephalograms|
|US4938218 *||28 Oct 1988||3 Jul 1990||Nellcor Incorporated||Perinatal pulse oximetry sensor|
|US4944307 *||22 Aug 1988||31 Jul 1990||The Hon Group||Intrauterine catheter|
|US5050613 *||15 Sep 1989||24 Sep 1991||Imex Corporation||Method and apparatus for vascular testing|
|US5099842 *||4 Apr 1990||31 Mar 1992||Nellcor Incorporated||Perinatal pulse oximetry probe|
|US5109849 *||21 Feb 1990||5 May 1992||Nellcor, Inc.||Perinatal pulse oximetry sensor|
|US5139033 *||4 Mar 1991||18 Aug 1992||Cardiac Pacemakers, Inc.||Sutureless myocardial lead implantation device|
|US5154175 *||4 Mar 1991||13 Oct 1992||Gunther Ted J||Intrauterine fetal EKG-oximetry cable apparatus|
|US5184619 *||2 Oct 1987||9 Feb 1993||Peritronics Medical, Inc.||Intrauterine pressure and fetal heart rate sensor|
|US5188108 *||23 Jan 1991||23 Feb 1993||Hewlett-Packard Company||Sensor, apparatus and method for non-invasive measurement of oxygen saturation|
|US5205296 *||19 May 1992||27 Apr 1993||Hewlett-Packard Company||Uterine contraction detection|
|US5217013 *||6 Jun 1991||8 Jun 1993||Somanetics Corporation||Patient sensor for optical cerebral oximeter and the like|
|US5224478 *||25 Aug 1992||6 Jul 1993||Colin Electronics Co., Ltd.||Reflecting-type oxymeter probe|
|US5246003 *||19 Feb 1992||21 Sep 1993||Nellcor Incorporated||Disposable pulse oximeter sensor|
|US5247932 *||11 Oct 1991||28 Sep 1993||Nellcor Incorporated||Sensor for intrauterine use|
|US5279308 *||19 Feb 1993||18 Jan 1994||Graphic Controls Corporation||Intrauterine pressure catheter system|
|US5373852 *||25 Jun 1993||20 Dec 1994||The Regents Of The University Of California||Monitoring uterine contractions by radiotelemetric transmission|
|US5377673 *||22 Mar 1993||3 Jan 1995||Van Dell; Peter||Intrauterine monitoring device|
|US5419322 *||22 Jul 1993||30 May 1995||Joseph; Barry M.||Internal apparatus for continuous electrical and oximetric intrapartum monitoring of the fetus|
|US5421329 *||1 Apr 1994||6 Jun 1995||Nellcor, Inc.||Pulse oximeter sensor optimized for low saturation|
|US5497771 *||30 Mar 1994||12 Mar 1996||Mipm Mammendorfer Institut Fuer Physik Und Medizin Gmbh||Apparatus for measuring the oxygen saturation of fetuses during childbirth|
|US5551424 *||7 Jun 1995||3 Sep 1996||Phox Medical Optics, Inc.||Fetal probe apparatus|
|US5743260 *||17 Mar 1995||28 Apr 1998||Nellcor Puritan Bennett Incorporated||Fetal pulse oximetry apparatus and method of use|
|CA2115715A1 *||15 Feb 1994||17 Aug 1994||Gerhard Rall||Sensor device for measuring vital parameters of a fetus during labor and delivery|
|DE2619471A1 *||3 May 1976||24 Nov 1977||Albert Prof Dr Huch||Intra-uterine surface temp. measuring probe - is made from a probe material of low thermal conductivity|
|DE2749048A1 *||2 Nov 1977||3 May 1979||Siemens Ag||EEG electrode head for foetus - incorporates recess with supply line for discharging treatment fluid in contact region|
|DE3810008C1 *||24 Mar 1988||26 Oct 1989||Johannes Dr. 8000 Muenchen De Buschmann||Title not available|
|DE4304693A1 *||16 Feb 1993||18 Aug 1994||Rall Gerhard||Sensoreinrichtung zum Messen von vitalen Parametern eines Feten während der Geburt|
|DE4407541A1 *||7 Mar 1994||6 Oct 1994||Mipm Mammendorfer Inst Fuer Ph||Apparatus for measuring the oxygen saturation of fetuses during birth|
|EP0097454A2 *||9 Jun 1983||4 Jan 1984||Ben-Gurion University Of The Negev Research And Development Authority||Method and device for measuring intrauterine pressure|
|EP0135840A2 *||29 Aug 1984||3 Apr 1985||Nellcor Incorporated||Perinatal oximeter|
|EP0442011A1 *||15 Feb 1990||21 Aug 1991||Hewlett-Packard GmbH||Sensor, apparatus and method for non-invasive measurement of oxygen saturation|
|EP0451560A2 *||20 Mar 1991||16 Oct 1991||PPG Hellige GmbH||Apparatus for monitoring respiration|
|EP0522674A2 *||10 Jul 1992||13 Jan 1993||Mark R. Robinson||Oximeter for reliable clinical determination of blood oxygen saturation in a fetus|
|EP0586025A2 *||30 Jun 1993||9 Mar 1994||Robinson, Mark R.||Reliable noninvasive measurement of blood gases|
|EP1046192A1 *||22 Sep 1999||25 Oct 2000||Philips Electronics N.V.||Method of manufacturing a semiconductor device in a silicon body, a surface of said silicon body being provided with an alignment grating and an at least partially recessed oxide pattern|
|WO1989009016A1 *||24 Feb 1989||5 Oct 1989||Johannes Buschmann||Process and device for measuring the radiation absorbed by a tissue|
|WO1990001293A1 *||14 Aug 1989||22 Feb 1990||Jason Otto Gardosi||Fetal probe|
|WO1990004352A1 *||27 Oct 1989||3 May 1990||Nellcor Inc||Improved perinatal pulse oximetry sensor|
|WO1993018703A1 *||12 Mar 1993||30 Sep 1993||John S Missanelli||Peripartum oximetric monitoring apparatus|
|1||"Konig, Volker, FIG. 1-copy of slide shown in Kloster Banz, 8623 Staffelstein, Sep. 27-30, 1992".|
|2||"Noninvasie Pulse Oximetry Utilizing Skin Reflectance Photoplethysmography", IEEE Transactions on Biomedical Engineering, vol. 35, No. 10, pp. 798-805, Oct. 1988.|
|3||*||K o nig, Volker, FIG. 1 copy of slide shown in Kloster Banz, 8623 Staffelstein, Sep. 27 30, 1992 .|
|4||*||Noninvasie Pulse Oximetry Utilizing Skin Reflectance Photoplethysmography , IEEE Transactions on Biomedical Engineering, vol. 35, No. 10, pp. 798 805, Oct. 1988.|
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|US7047055 *||26 Jan 2001||16 May 2006||The General Hospital Corporation||Fetal pulse oximetry|
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|U.S. Classification||600/313, 600/338|
|International Classification||A61B5/0448, A61B5/00, A61B5/024|
|Cooperative Classification||A61B5/6839, A61B5/0448, A61B5/14542, A61B5/4362, A61B5/4356, A61B5/1464, A61B5/6848, A61B5/02411|
|European Classification||A61B5/1464, A61B5/145N, A61B5/68B3N, A61B5/68D1B, A61B5/43F6E, A61B5/43F6C, A61B5/024B, A61B5/0448|
|10 Sep 1997||AS||Assignment|
Owner name: GERHARD, GERMANY
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:RALL, GERHARD;REEL/FRAME:008827/0131
Effective date: 19970731
Owner name: KNITZA, REINHOLD, GERMANY
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:RALL, GERHARD;REEL/FRAME:008827/0131
Effective date: 19970731
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Year of fee payment: 12